Lubricating and oil seal system for a high speed compressor

Abstract

A high speed centrifugal compressor is closely directly coupled to the power turbine of a two-shaft gas turbine having a gas generator section separate from its power turbine. Through the direct close coupling and center-line mounting of the gas turbine exhaust casing for free and uniform heat expansion, alignment between stationary and rotating parts of the power turbine and compressor is maintained free from mechanical problems. Bearings and oil seals are fed by an integrated lubrication and a sealing oil system utilizing a compact oil distribution manifold assembly incorporating a quick filter change structure. The gas turbine-compressor finds particularly useful application in areas where high power, compact, relatively maintenance-free units are required, as, for example, on offshore platforms in the natural gas industry.

I claim: 
     
       1. An integrated oil system for providing lubricating and sealing oil to the bearings and oil seals of a gas compressor comprising a reservoir means containing thhe system oil, pump means for pumping the system oil at a pressure higher than the pressure of the gas in the compressor, seal oil feed means for conducting this higher pressure oil to the oil seals of the compressor, oil pressure reducing means for taking a portion of the higher pressure oil and reducing its pressure to a pressure lower than the pressure of the gas in the compressor suitable for lubricating bearings, lubrication oil feed means for conducting this lower pressure oil to the bearings of the compressor for lubrication thereof, and drain means for draining the oil from the bearings and seals back to the reservoir means. 
     
     
       2. An integrated oil system as claimed in claim 1 further including means for cooling the lower pressure oil prior to conducting it to the compressor bearings. 
     
     
       3. An integrated oil system as claimed in claim 2 wherein the cooling means comprises a cooling coil, a cooling fan and a hydraulic motor means for driving the cooling fan, further including hydraulic oil feed means for conducting system oil to the hydraulic motor to operate it. 
     
     
       4. An integrated oil system as claimed in claim 3 wherein the hydraulic oil feed means includes oil pressure reducing means for taking a portion of the higher pressure oil and reducing its pressure to a pressure sufficiently low to avoid damage to the hydraulic motor but sufficiently high to operate the motor, and means for conducting the oil exiting the hydraulic motor to the bearings of the compressor for lubrication thereof. 
     
     
       5. An integrated oil system as claimed in claim 4 further including means for conducting at least a portion of the oil exiting the hydraulic motor through the cooling coil prior to conducting it to the compressor bearings. 
     
     
       6. An integrated oil system as claimed in claim 5 further including temperature sensing means for sensing the temperature of lubricating oil to be conducted to the compressor bearings, signalling means for transmitting a signal relating to temperature sensed, control means responsive to the temperature signal for controlling the lubricating oil temperature, the control means including regulating valve means for regulating oil flow through the cooling means. 
     
     
       7. An integrated oil system as claimed in claim 1 further comprising high pressure oil filter means for filtering the higher pressure oil, lower pressure oil filtering means for filtering lower pressure oil, spare filter means capable of filtering either higher or lower pressure oil and valve means interconnecting all filter means, the valve means including means for transferring flow of oil from either the higher or lower pressure filter means to the spare filter means, without affecting the oil flow in the other filter means and without interrupting oil flow in the system. 
     
     
       8. A combination bearing and oil seal for the compressor unit as claimed in claim 1 wherein the compressor casing means includes an end cover in which is mounted a first cartridge assembly means within which the rotor assembly is mounted, the first cartridge assembly means comprising a cartridge housing, high speed thrust and journal bearing means and high pressure mechanical oil seal means, second cartridge assembly means mounted in the compressor casing means where the compressor shaft means extends therethrough, the second cartridge assembly means comprising a cartridge housing, high speed journal bearing means and high pressure mechanical oil seal means. 
     
     
       9. A combination bearing and oil seal as claimed in claim 8 wherein the cartridge assembly means include pressure reducing means for reducing the pressure of high pressure sealing oil to a pressure suitable for lubricating the bearing means therein.